The present invention pertains to electrical connectors, and in particular, to an extruded metallic electrical connector assembly that allows for the connection of optical fibers and/or electrical wires.
Electrical connectors are used in many different types of electrical and electronic systems. They come in various sizes depending on the physical and electrical parameter of the installation. Some high-speed digital signal applications require multiple contact connectors in a single rectangular module that are held together and stackable without distorting or adversely modifying the signal intelligence. Digital signals must have a high degree of signal integrity on entering and exiting an electrical connector system. Requirements for connector types, in increasingly high-speed applications include a high degree of shielding, preventing signal distortion from outside Electromagnetic Interference (EMI) and low inductance and resistance for signal and return signal paths.
Rectangular connectors with multiple contacts that are two millimeter (2 mm) or less in center spacing have limits in contact density and signal shielding by currently employed manufacturing processes. However, electronic systems that use high-speed connectors continue to shrink in physical size and require increasing signal density reducing physical size requirements for connectors. Current rectangular connectors having a plurality of contacts have limits in providing dense signal packaging and shielding of each individual contact within the connector-housing module.
Although classical round coaxial connectors have contiguous shielding, along the contact length and provide low inductance and good signal integrity, they do not offer the plurality of contacts, particularly for densities of 2 mm or less in a rectangular configuration. In round coaxial connections, multiple contiguous contacts cannot be densely packed or stacked in a module form to densities attainable in a rectangular configuration and still have each signal contact surrounded with in a metal enclosure along the length of the contact. Connectors of a rectangular shape, having a plurality of contacts 2 mm or less for high-speed signal application, use a combination of injection molded plastics either riveted or press fitted to metal plates to simulate shielding and reduce inductance and resistance to improve signal integrity. However, these connector systems, while providing greater contact densities than round coaxial connectors, do not provide a contiguous metal cavity along the length of each individual contact. Instead only one or two sides of each individual contact has a shield vs. all 4 sides of the extruded connector-housing module described here.
Presently, most high-density connectors are either electrical or optical. Some fiber optic interfaces occur at the printed circuit board level and convert the electrical signal to light (optical) signals through devices such as a vertical cavity surface emitting lasers (VCSELs), whereby the electrical high speed signal is converted into high-speed modulated light signal. However, there is a need for a truly cost-effective, high-density and easy to manufacture hybrid electrical-optical connector.
Further, electrical and electrical-optical hybrid connectors can suffer from Joule heating, which can damage the connector and its components. Accordingly, it is desirable to have a system and method for cooling the connector.
The present invention pertains to electrical connectors, and in particular, to an extruded metallic electrical connector assembly that allows for the connection of optical fibers and/or electrical wires.
An example embodiment of the invention is a rectangular connector having a plurality of contacts, with each contact being enclosed in a metal shield along the contact length. The assembly has a rectangular metallic housing that contains a plurality of contact channels through which the contacts are inserted. The contacts are insulated from the surrounding housing by a coating on the inside of the housing. The contacts are connected at one end of the housing to an intermediate printed circuit board. The other end of the housing forms the mate to a receptacle mounted on the motherboard of an electronic system. The housing assemblies are stackable because of their shape. The invention also includes a hybrid electrical-optical connector that employs VCSEL technology, so that both electrical and optical connections can be accommodated in the same connector. Further, the connector can include a connector cooling system to cool the connector.